Solving Trigonometric Equations Using the Quadratic Formula - Example 2

[@fauxpas4589]

Thank you so much! far better than my teacher!

[@Uvuv6969]

Ratio

[@bryceee99]

Very helpful -- great video, thank you!

[@arstgkneio]

If I have 2cos^2x can i say that it is interchangeable with 2(1-sin^2x)?

[@synunn]

cheers, this video just fixed a 2.5hour headache!

[@rawsuperstar100]

Thank you my friend this was very helpful

[@mathdoris]

@jsm666 That is not why, H0SS302. The reason you can't say +/- 68.13 degrees is because the problem asked for the solutions ONLY between 0 and 2 pi. Although -68.13 is technically would work, it is not between 0 and 2 pi which the problem is requesting.

[@mendicant1981]

Great Stuff, thank you

[@AA-ll4lu]

When u bring over the one why did it not change to -1 ?

[@quintinmagill4485]

how would i do an equation that goes like cos x (2 sin x - root3) = 0

[@superwhine]

I am sorry for you loss brother, never did find the answer did you?

[@Trust102]

how did you do cos inverse of cos theta on your calculator?

[@Skywalker96214]

Hi Patrick, can you give some examples of solving systems of trig equations I need to find both x and y for arcsin x arcsin y = pi^2/12 arccos x arccos y = pi^2/24 please help me out. If you didnt reply soon enough then probably means I failed the quiz, because i a quiz over it tomorrow, and my teacher haven't teach this yet. however, i still with you can do some videos about this kind of problems, at least that would help other people and i will come back to learn this.

[@sakshiraj4261]

I just love this videos

[@srishtiarya9863]

Hey so by "distributing the negative" what did you mean? If you multiply the entire equation by -1 to make the cos^2theta into positive (because at the start it was 1-cos^2theta, hence negative and we can't work with that very well) then the entire quadratic is reversed :. 5costheta-1-cos^2theta=1 =>-5costheta+1+cos^2theta=1 OR cos^2theta-5costheta=0 (+1 and -1 cancel out) or am I really wrong? (i get that wrong a lot)

[@AA-ll4lu]

Why didnt he change the 1 to negative 1 when u moved it to the left of the equal sign ? Or am i wrong ?

[@azizkash286]

bless this man

[@rileywolfe5036]

Thx for the help

[@pillowyflunky9931]

thanks

[@crabnebula1816]

I completely forgot about the quadratic equation lmao

[@fatimaahmad8702]

Thank you, very helpful!

[@gidiemami]

I like it

[@RocanMotor]

@kagomeh14cynthy lefties are annoying? what the hell gives you that notion? And I'm a righty, before you think I'm defending lefties for personal reasons.

[@toastburntbread]

i'm crying because this is so easy, and I have spent two days trying to solve for theta without using the quadratic formula, for i thought you couldn't use it with trigonometric functions. :( I AM SO SAD.